Various experimental researches were conducted dealing with physical
characteristics and sensation in order to be able to express quantitatively
appropriate hardness in terms of comfortability in residential floors. From
among these, the results of analyses of impact force time characteristics of a
sole by footsteps and the production of a prototype impact source involving the
impact force of the heel, which is a representative impact force generated by
footsteps are indicated in this paper. Then, using the impact source to measure
the amount of dynamic displacement in wooden floors of old construction and in
the direct-pasted wood flooring commonly used in recent multifamily housing, the
dynamic spring coefficient of traditional wood-construction floor structure,
which had never before been clarified, was quantitatively determined.